The present invention relates generally to systems and methods for auditing the performance of remote (also called open path) vehicle emissions sensing systems. More specifically, the present invention relates to an audit vehicle and audit method that can be used to drive through a remote vehicle emissions sensing system whole releasing a known quantity and mixture of gas to test the performance of the sensing system.
Systems are known in the art for detecting the tail pipe emissions or exhaust plumes of the vehicles as they drive on a vehicle path such as a roadway. For example, it is known for a light beam to be projected across the roadway and received by a receiver that analyzes the received light and determines the components of the vehicles emissions. In order to test the performance of such systems, it is desirable to have a vehicle that emits known volumes, mixtures, and concentrations of gases and that can be driven through the sensing system in order to test the detection performance of the system.
It is therefore a feature and advantage of the present invention to provide a vehicle that emits known volumes, mixtures, and concentrations of gases and that can be driven through the system in order to test the detection performance of the system.
It is another feature and advantage of the present invention to provide a method for testing or auditing vehicle emissions sensing systems.
The above and other features and advantages are achieved through the use of a novel apparatus and method as herein disclosed. In accordance with one embodiment of the present invention, an apparatus for dispensing gas from a vehicle has a plurality of compressed gas cylinders filled with known concentrations of gases, referred to also as xe2x80x9cgas bottlesxe2x80x9d; a plurality of shutoff valves, one valve associated with each of the gas bottle for controlling gas flow out of that gas bottle; a manifold that receives gas from each of the shutoff valves and leads to a single pressure regulator; an output gas line leading from the pressure regulator; a master shutoff valve that controls the release of the audit gas; and a sample gas outlet opening at the end of the output line with flow through the output line measured.
In accordance with another embodiment of the present invention, a system for recording telemetry data associated with a remote emissions audit vehicle, includes: a central computer; and at least one telemetry sensing device comprising at least one of: a vehicle speed sensor mounted at a non-drive wheel; a global positioning system sensor; ambient atmospheric condition sensors; an infrared beam detector; and an output gas flow rate sensor. Data from at least one sensing device is stored by the computer.
In accordance with another embodiment of the present invention, a method for recording data related to the telemetry of an audit vehicle is provided. The method includes driving the audit vehicle past a remote emissions sensor while emitting a sample blend gas; and recording telemetry data relating to the audit vehicle. The telemetry data includes at least one of: vehicle speed read by a sensor on a non-drive wheel, GPS information, atmospheric information, IR light information, road temperature sensing information, and gas flow rate information.
In another embodiment of the present invention, a method of controlling gases emitted by an audit vehicle, includes controlling a plurality of operated valves each associated with a bottle; driving the audit vehicle past a remote sensing device; and recording data related to the audit path.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.